Vibration absorbing mounting



April 13, 1948. c. HUSSMAN v VIBRATION ABSORBING MOUNTING i i I I I l I i i I I N V EN TOR. W440 Filed May 17, 1946 hav m "quencies.

Patented Apr. 13, 1948 a UNITED NIBRAfiI-ION Ansonnnre Mot-mm l sweet esteeme- 1 i lieet' en-M- t, 1946, {Serial 1 0. $10,553

This invention relates to vibration absorbing mountings. l i

' -In theuse of business or ofifice maohines s'uch as some motor driven-tabulating machines," mailing machines, 'tiuplicatihg machines andthe like, frequently the yibrations resulting from opera-- "ti'ohoi the machines are very objeotion ahl e n'ot I only to Workers in the immediate location of l the same bi1ildings. Such motor operated mae'hiiis aregrather bulkygenerally and may Weigh e'ral 'h red pounds andyrestinglupon thefloor of [ah offiee, have presented vibration absorbing firohlems that have been di fiieultto olve. {One reasonfor the difficulty-is? the iaotfthat such ma- 0' sgenerate ilorations that range from rela- Awn or eb n inexmeie ie h eb e ife nd that will give equal eorrectio'n against the trans- Pre Jse o exem eien o' m r l hebei may be slightly compressed; thus not affordin the maximum high --f requency absorption of which the particular material is palpable, while I the other pads may be oomp'ressedibeyond their elastic limits and thus afford little or no protecftion against transmission 15: either high low frequency Vibrations.

The use of metallic springs in providing a I floating mounting $9 sueh maehines also presented difiioulties 'since springs, which while under compression provide excellent "m'ans 'for isolating low frequency vibrations,afford-but little absorbing value insofar 'as"'-hi-ghfrequently vibrations are concerned and a floating mounting" offers but little stabilizing resistance to: fside wel 1 3 Notwithstanding that-such Jot-1siness machines and many other types of machines with which the present improvements are adapted for use,

usually do not have their total weights dis- -=tiibuted "for support equally by the legs of the machineyit- -is quite essential-that any-vibration absorbing; mounting structure for-such maohine 4 be 'oapable of supporting thet machine 1in the 1 suc we ,eent niie tem e l el .me fiien m ge t in r P pe o t e eratb el 51 .e si i l b ep d .foree u e ete pee uee .quri i v pe ien o 1; .suchtnea n whi h' eeeie eus e -swa that-i t se .etert me Q h liel r l i oriz nta dire t ns 9 hen e teeet t eee in supp rt r'wh eh tee p.9 uppress su inoriaon e meiem ni i eernell ew e se Iei en ebi e e FlAL-P EE P1 V nF PF P ev de e iv b ret en e e :eeie ebeerbine me niie "i meehin th I t e wel n e W 1 as for machines of other types, which is capalole of -2 .ebsorbi ei eeeh e rfi u eey br n which,

lilgejepro e as well as relatiyely low ilgratio w ieh maypro- Qbie t o the inyen ie i .110, P1"?- eenti epretid -xthetlsepmees swa n t PP IQ ma h ne wh l i ,l o eme of tile flfiihih n transm sion ra .rili m u eea th me to he sum -n i e stnes tibr i en .tha -;e. :e in iden ,-.du sue swe y e L'themachine.

rhe q iel m v ment of 80 ,Anotlgeriiqlgjept .9: th intention :ieL Q. rw e yibraition absorhing.mountin e that is adju tabl for .raisin or\,j .owerl.n the isnpe iaeen l por io s otathegs ppontei mae i .su res. th le s e ,icomers. pi the.;base. otthemaehin wh reby t efitmaehinefcan t-beladiysted .t i-a pro er upe a .;leye1,;without; impairing-the; vi r t on a sorb I:eharaeteristicsoithemountins.

q qtheryfeat ures,.ofithe invention relate to; featur'es of. construction; andlarran ement of parts 1, 'w e willi:b .ep arent ir mi .e ns dereti of thegfellowin specificat o w nd gaceempany ne .idr winss,,whe tein,

Fi ure t .amhrplgenezside,elevation of; an imspro e ;rmquntinsistmeture t at, s illus a iv o thetint nti aone:of; th two v b io abs 1ringiunits lllustil m tm12 fi ur ein sh w in tir iealls ie Ri 1 h etiq pla rie o t m rove mounting, a machine g;four supporting legs, ees v m h ne. being M indicated; d eeramme mum psit on e t .;-mounting.

i Eigifiiis a bnokenrhottemt anlyiew of one of ttheiitour ,yibration .msulatin units (show n He time t at te t n one side of the machine resting in the two seats l2 of one of the two mounting sections and the two legs at the other side of the machine resting.

in the two seats I 2 of the other mounting section. The two seats |2 of each section |3 are spaced 4 felt pad or the like 25 which in turn rests upon the plate. A second spring retainer 26 is positioned over the upper end of the spring and is provided with an aperture through which extends the upper threaded end of the stud 22. A washer 21 is shown on the retainer beneath the nut 28 while a lock or jam nut 29 is shown above the nut 28 to lock the latter in adjusted position.

Between the end of the bar I4 and the plate |8 as viewed in the sectional unit of Fig. 1, there is provided a stabilizer member 3|! which preferably .is a block or'pad of organic vibration absorbing material such as natural cork. The block 30 has position. The block has an upper and lower surapart upon a bar M the requisitedistancefor re-' Vibration absorbing units I! are provided for supporting the ends of the bars M. The units l-l are of similar construction and the details of one of the same are shown in section in Fig. 1 and one of the units only will be described in detail. I

Each of the units I! referred to comprises a plate |8 provided with a central opening Hi therein. To the lower surface of the plate I8 is secured a rail 20 shaped as illustrated in Fig. 3, to provide a confining socket for a, highirequency vibration insulator 2| which in use may rest directly upon a floor or other supporting structure; Such insulator preferably comprises natural cork, and in Fig. 3 the insulator is shown as comprising 3 cork slabs 2, 2|, 2| of proper lengths and thickness to fit snugly in the relation shown in Fig. 3 for confinement by the rail 20. The height of the slabs is greater than that of the rails whereby the total weight of the mounting and the machine resting thereon is borne by the insulators 2| of the four units H. The height of the insulators 2| and the thickness and length thereof are important since the'efiiciency-of an organic insulating material, such as cork, in absorbing vibrations increases as the material is compressed, provided the degree of compression is short of the elastic limit of the material. Hence, a proper mass of cork for each insulator is desirable. Thus, where the weight of the machine supported by the improved insulating structure is from 500 to 600 lbs. and the cork slabs are approximately thick and 1%" in height and having a combined length of 10 to 11 inches in each unit,'there will be an average vertical compression of the slabs of approximately which is short of the elastic limit of the mass of cork provided and the insulators will absorb a high proportion of those relatively high frequency vibrations from the machine which, if transmitted to the floor would produce objectionable noise.

Secured to the adjacent end'of the bar M, as shown in Fig. l, is an upstanding stud 22 that passes through the opening I9 in the plate l4 and around which stud ispositioned a compression spring 23. The lower end of the spring is mounted on a spring cup or retainer 24 which rests upona face substantiallygreater in area than the area of the aperture I!) while below the block is a disc or washer-like member 3| having a diameter the same as that of the aperture.

When a machine In is placed upon the mounting sections, the weight of the machine tends to compress the springs and lower the bar. Since the weight of such a machine is not equally distributed generally, the springs may not all be compressed equally and hence the machine may not stand at the desired level, To level the machine, the nuts 32 of the units I! are tightened, or such of them as may be necessary to cause the machine to stand at a proper operating level. If

necessary, all the nuts 32' will be tightened or screwed downwardly not only to level the machine but to compress the springs 23 and thereby effect a compression of the blocks 30. As shown in Fig. 1, the disc 3| is of the samediameter as the aperture |9, and by reason of the compressive force exerted against a superja-cent portion of the block 30, the disc causes a cylindrical portion of the block to protrude upward slightly into the aperture. Such stressing of the blocks in shear enables them to exert a stabilizingefl'ect by resisting horizontal vibratory movement of the sussince without an eilective means for restraining the machine against swaying movement, a vibration insulating mounting may-be impractical by renderingit difficult, if not impossible for the operator to operate the machine.

In selecting springs 23 of suitable compressive resistance for a machine ID of a given weight, it is desirable that the springs be sufficiently soft so that the proportion of the total load to be borne by the particular springs will effect substantial compression of the springs without contact of the adjacent turns'or convolutions thereof. Compression springs are most effective inabsorbing low frequency vibrations where the springs are under a high degree of compression, short of total compression. r

The springs employed must be sufliciently stiff or strongnot only to support the load imposed on each without becoming fully compressed but also sufiiciently stiff to enable the stabilizer members 30 to be'stressed in shear without efiecting total compression of the springs. Fromthe above it will be apparent that all the springs 30 ofa given ea-ass employed in seam-1a or units, 11 a an in- .stallafiion that are .to upport the heavier individual loadsimposed by .a machine 'or unequally distributed weight. By employing springs of com- .pjressive resistance values thatlare relatively pro- .por'tional "to theloadsto be imposed thereon all 'fipia'ctioal matter, however, 'satis'factorvresults generany will be attained where the springs are substantially of uniform stiffness, .provided'rion'e ofthem becomes fully compressed in use.

The improved vibration absorbing mounting illustrated, as will be noted, elevates the machine T but a short distance above the floor, generally 7 less than an inch wherethe flanges of the'channel jbars 1'4 are "approximately /3" in vertical dimension. By inverting the channel bars I l the vertical spacing of the machine above the floor canbe reduced. Hence, use of the improvements is not objectionable to the machine operators as frequently is the case Where an insulating mountinga-lters by several inches the normal operating level of a machine.

It will also be noted that the U-shaped base formed by the rails and the vibrator insulators 2| of the unit I! provides 'a'space into which extends the "adjacent end of the. respectivefsupmortingbar 13; The bar, 'asindicatedinFig. 3 *is'of less 'widththan'the distance between the parallel arms of the U-shaped base and hence vibrations from the bar are not transmissible to the base except through the stud 22, which as above explained, is effectually insulated by tandemly arranged low and high frequency absorbing elements 23 and 25 against transmission of the vibrations to the unit and thence to the floor. Likewise such arrangement is of advantage in that the supported ends of the bar are disposed directly beneath the insulators 23, 25, and which enables the supporting studs to be suspended vertically for avoiding distortion of the parts of the units. Hence, in instances where insulators 23, 25, or 30 or any of them must be made of greater vertical dimensions than those shown for illustrative purposes by reason of the weight of a particular machine to be supported by the mounting relatively longer studs 22 may be employed for spacing the bars M a minimum distance above the floor and thereby avoid altering substantially the preferred operating level of the machine.

While I have shown and described a structure that is illustrative of the invention, it will be seen that various changes in the details of the disclosures may be resorted to without departure from the spirit of the invention.

I claim:

1. A vibration insulating mounting for a machine comprising a pair of bars constituting a machine support, and vibration insulating units supporting said bars and each comprising an apertured plate above a, portion of the bar and provided with downwardly extending floor contacting high frequency insulating means for spacing the bars above the floor, a compressible low frequency vibration absorbing member supported by the plate, a stud secured at one end to the bar and extending upwardly through the aperture of the plate and at the upper portion attached for support to theupper portion of said low frequency vibration absorbing member, a high frequency vibration absorbing element between the apertured portion of said plate and subjacent portion of the bar, said element being of greater area than the area of said aperture, and adjusting means for said. stud whereby thesupported portion ofthe bar can beelevated relative to said plate 'for stressing in fshear the portion of said high frequency absorbing element that registers withsaid aperture for effecting stabilization of "the'baragainst, vibratory movements inhorizontal directions.

25A vibration insulating 11101111111112. provided With" a machine supporting base comprising a pair of bars provided with upstandmg studs at the ends-thereof, and vibration insulating units'each cooperating'with one of said studsflf'or supporting the bars above afioo'r, .each of said units comprising a horizontal plate provided with can aperture of greater diameter than the diameter of the studs and through which aperture the respective stud extends, a low frequency vibration absorbing element above the plate operatively attached to Ithelupper portion of the respective. stud and adapted to be placed under partialcompression by the load imposed Ionthebase'a high frequency (absorbing element surrounding said stud between ,sa'id .plate and bar of greater'horizonta'l ,area.

than said aperture, a shear memberbeneath said high frequencyabsorbing element, and adjusting:

, meansonfthe stud for increasingthe compressive W stress onthe low frequency absorbing element and cooperating withsaid shear'niember'for stressing in shear the portion of said highfre'quency element positioned directly beneath said aperture for effecting stabilization of the base against horizontal vibratory movements.

3. A vibration insulating mounting provided with a machine supporting base comprising a pair of bars provided with upstanding studs adjacent the ends thereof, and vibration insulating units each adapted for cooperation with one of said studs for supporting said bars above a floor, said units comprising a horizontal plate provided with downwardly extending floor-contacting vibration absorbing means, a high frequency vibration absorbing pad on said plate, a low frequency vibration absorbing spring supported on said pad, said plate having an aperture therein of greater diameter than the diameter of the respective stud and through which aperture said stud extends, adjusting means operatively attaching the upper portion of the stud to the upper portion of said spring whereby the stud is suspended from the spring and enabling the stud and adjacent portion of the respective bar to be adjusted vertically with respect to the plate, a compressible vibration absorbing element disposed between said bar and plate of a facial area greater than the area of the aperture, and a shear member beneath said element of the diameter of said aperture for stressing in shear the portion of the element aligned with said aperture as said stud is moved relatively upward through said aperture b said adjusting means.

4. A vibration absorbing mounting comprising a machine supporting base, a plurality of vibration absorbing units each comprising a plate provided with a floor-contacting member, suspending means supported by the respective plates for suspending the base above a floor and comprising vibration absorbing elements for absorbing vibrations that tend to travel from the base downwardly through the units, and a vibration absorb- Ling element in each unit arranged to stabilize the respective base-suspending means" against the induction of lateral oscillatory movements in the suspending means by horizontally traveling vibra tory impulses transmitted to the suspending means from said'base, V

5. A vibration insulating mounting comprising a machine support having engageable. end portions, a plurality of vibration insulating units each comprising a vibration absorbing element arranged for compression in a vertical direction, each unit comprising a base open at one side for accommodating insertion of one of said end portions of the support into a position axially beneath the respective element, and suspending means for each end portion of said support comprising a member engaging one of said end portions and supported by one of said elements and of a length to space the support above a floor.

6. A vibration insulating unit comprising an apertured horizontal plate provided with depend- 1 ing members defining a holder for a floor contacting vibration insulator having an open'side for accommodating beneath said plate a laterally inserted'portion of a machine supporting base, and a vertically deflectably vibration insulating means mountedon said plate for supporting a vertically arranged suspending mem'ber'passing through said aperture into engagement with'a portion of a machine supporting base beneath said plate. 7

7. A vibration insulating unit comprising an apertured horizontal plate provided on the lower surface with a floor contacting vibration insulator having an open side for accommodating the lateral insertion beneath said plate of an engage I able portion of a machine supporting base, and defiectable low frequency and high frequency vibration absorbing elements arranged in tandem upon said plate coaxially with respect to the aperture thereof for supporting asuspension member extending through said aperture into engagement with'a subjacent engageable portion of a machine supporting base.

8. A vibration insulating unit comprising an apertured horizontal plate provided on the lower surface with a floor contacting vibration insulator, said insulator being of' U shape providing an open side for accommodating lateral insertion 15 'beneath' said plate of an engageable portion of a machine supporting base, a stud engaging said portion of the base and extending upwardly through said aperture out of contact with the wall thereof, compressible vibration absorbing means on said plate annularly disposed about said stud, and means supported by said absorbing means and engaging said stud for suspendingly supporting the latter and the portion of the base engaged thereby.

V CARL HUSSMAN.

REFERENC S CITED The followingreferences are of record in the file of this patent:

3 UNITED STATES PATENTS" Number 7 Name Date" 1,763,682 Wallace June 17, 1930 1,880,280 Replogle Oct. 4, 1932 35 2,144,848 'Miller Ja1 .24,1939 

